The research described in this project is directed toward elucidating the structure and mechanism of the enzyme formyltetrahydrofolate synthetase. Experiments are designed to: 1. Determine the mechanism of the catalyzed reaction. 2. Identify amino acid residues at the active site. 3. Determine the mechanism by which specific monovalent cations induce the association of monomers of the protein. BIBLIOGRAPHIC REFERENCES: D. H. Buttlaire, G. H. Reed and R. H. Himes. Equilibrium and water proton relaxation rate enhancement properties of formyltetrahydrofolate synthetase-manganous ion-substrate complexes. J. Biol. Chem. 250, 254 (1975). D. H. Buttlaire, G. H. Reed and R. H. Himes. Electron paramagnetic resonance and water proton relaxation rate studies of formyltetrahydro-synthetase-manganous ion complexes. Evidence for involvement of substrates in the promotion of a catalytically competent active site. J. Biol. Chem. 250,261 (1975).